This invention relates to a process for separating a 2-oxazoline from an aqueous solution. More specifically, this invention employs a selectively permeable membrane to separate the oxazoline.
The art has long sought a method for the separation of a 2-oxazoline from an aqueous solution. However, the methods taught in the prior art suffer from one or more deficiencies.
It is recognized in U.S. Pat. No. 3,402,107 that the separation of water from a 2-oxazoline by distillation is difficult due to the formation of azeotropic mixtures of the oxazoline with water. These difficulties can be overcome by adding to the distillation mixture an organic solvent which forms an azeotrope with water, but this patented process is energy intensive.
British Pat. No. 1,502,562 describes a process for separating a weak base from an aqueous solution. In this process, the weak base permeates through a selectively permeable membrane to produce a concentrated solution of the base with a complexing agent on the other side of the membrane. Although 2-oxazolines are not enumerated as bases in this patent, these compounds are known to be weak bases. However, the 2-oxazolines would undergo hydrolysis in the presence of the acidic complexing agents employed in the reference process.